1. Field of the Invention
The present invention relates to a large wind turbine for generating electrical power, the wind turbine being mounted on a floating platform intended for use in a body of water, in which the floating barge also acts to support the rotor blade assembly, eliminating the need for bearings and allowing for extremely large wind turbine structures.
2. Description of Related Art including Information Disclosed Under 37 CFR 1.97 and 1.98
Prior art wind turbines come in many shapes and sizes. Vertical axis rotating blades are well known for use in electric power generation using wind. These generators can be mounted on land or on a floating barge over water. In order to generate larger electric power, the blades become extremely large, sometimes in the length of 100 meters each. As the blades become larger, the stresses that occur become so large that the modern materials used to form the rotor and blade become over-stressed. Thus, there is a limit as to how large a blade can be, and therefore there is a limit as to how much power can be produced by a single rotating structure.
One large wind turbine, which of U.S. Pat. No. 6,294,844 issued to Lagerwey on Sep. 9, 2001 shows a floating platform such as a barge or ship that supports a structure, the structure supporting a plurality of wind airfoils. The Lagerwey invention does not use a large wind airfoil, but makes use of a number of smaller airfoils. And additional embodiment shown in FIGS. 15A and 15B shows a vertical wind turbine rotatably supported by a floating ship. In this embodiment, bearings are used to support the rotating turbine, and therefore the size and weight of the rotating turbine is limited.
Another type of floating wind turbine is disclosed in U.S. Pat. No. 3,988,592 issued to Porter on Oct. 26, 1976, and discloses a floating sphere anchored to a sea bed, the sphere carrying a vertical axis wind turbine. The turbine is small and supported for rotation by bearings. As in the above mentioned Lagerwey invention, the invention of Porter is limited as to the size of the wind turbine because of the use of the bearings for rotational support.
Some prior art inventions make use of a floating turbine in which the turbine is located within the water. U.S. Pat. No. 6,734,576 issued to Pacheco on May 11, 2004 discloses in one embodiment a floating generator in which the rotary structure is completely submerged within the water flow path. The structure is supported by a floating barge.
There is a need in the art for a larger rotation device that can capture a large amount of wind to generate a large amount of electric power. It is therefore an object of the present invention to provide a large rotating structure to generator power from wind that does not require bearings to support the rotary structure. It is another object of the present invention to provide for a large airfoil surface such that the stress limitation of size in prior art rotating wind generators are not a limiting factor.